With the resignation of FIFA president Sepp Blatter amid a snowballing corruption scandal that has ensnared more than a half dozen officials, world soccer lurched into uncharted territory Tuesday.

Re-elected FIFA President Sepp Blatter arrives for a news conference after an extraordinary Executive Committee meeting in Zurich, Switzerland, May 30, 2015.

Blatter’s announcement, which came just days after he was re-elected head of the soccer's international governing organization, stunned the sporting world. It already had been reeling from the indictments unveiled last week by U.S. prosecutors.

Reaction ranged from restrained joy to smug satisfaction Tuesday as Blatter’s name and hashtags such as #BlatterOut rocketed to the top of Twitter and Facebook.

A number of commentators also questioned whether FIFA’s eyebrow-raising decision to award the 2018 and 2022 World Cup tournaments to Russia and Qatar might be open for discussion. Swiss authorities last week announced they were conducting a separate criminal investigation into how those sites were chosen.

"Change at the very top of FIFA is the necessary first step in delivering real reform of the organization," said Greg Dyke, head of Britain’s Football Association, which oversees the world’s wealthiest soccer league, the Premier League.

In comments later to The Guardian, Dyke went even further.

"He’s gone. At long last we can sort out FIFA. We can go back to looking at those two World Cups," he was quoted as saying. "If I were Qatar, right now I wouldn’t be feeling very comfortable."

Blatter wants 'best for FIFA'

At a hastily convened news conference at FIFA’s Zurich headquarters, Blatter, who will continue serving as president until a new one is elected, said in brief remarks that the organization needed profound restructuring.

"I appreciate and love FIFA more than anything else," he said. "And I only want to do the best for FIFA."

He refused to answer further questions.

Last Wednesday, Swiss authorities arrested several top soccer officials at a hotel in Zurich at the request of the United States, which indicted 14 people including several top FIFA executives.

Indictments announced that same day in New York listed 47 counts, including bribery, fraud and money laundering, accusing soccer officials of using FIFA business decisions to trade for personal wealth.

Blatter was not named in the indictments, though ABC News on Tuesday cited unnamed law enforcement sources as saying that indeed he was being investigated by the FBI.

Another FIFA official in media glare

Blatter’s announcement came on the same day that The New York Times published a story tying FIFA secretary general Jerome Valcke to 2008 payments that appear connected to South Africa’s bid to host the World Cup. U.S. investigators have said they believe the payments amounted to $10 million in bribes.

FIFA said the payments were approved in 2007 by Julio Grondona, chairman of the organization's finance committee at the time. Grondona died last year.

Clive Toye, who was the last commissioner of the North American Soccer League, said the fact that so many FIFA member countries voted to re-elect Blatter last Friday was an indication of FIFA’s deeper institutional problems with corruption.

The North American Soccer League was the first professional soccer league to have wide success on the continent before it stopped operating in 1985.

"I just think that indeed this may be the just beginning of the whole thing, because as I’ve said … why did those countries vote for [Blatter]?" Toye asked.

"Loyalty comes from a number of activities: love of country, love of game, love of person or love of dollars coming in so I can spend more money than my country makes in a year," he said. "If I was going to bet, I would bet there are more [indictments] to come."

Blatter's re-electionanalyzed

Jacob Frenkel, a former U.S. federal corruption prosecutor, said Blatter probably felt vindicated by being re-elected, even after news of the indictments emerged.

"Everyone knew, including Mr. Blatter, that this investigation was moving forward, was moving forward aggressively and had him personally in its sights. That does not mean by any means that he is about to be or will be indicted. We simply don’t know," Frenkel said. "But his personal vindication came from his re-election with the revelations about the $10 million payment...."

Chris Eaton, an analyst with the Sport Integrity at the International Institute for Sport Security, a Qatar-based research organization, called FIFA one of the most opaque organizations on the planet and said it needs to rethink how it runs itself.

"Really, [it's] a private monopoly, a private club that needs to grow up," he said.

"It needs to grow up into the real world of business affairs and translational/multinational business," Eaton said. "It needs to understand the need for accountability, transparency, best practices, know your customer, fit and proper practices."

For many soccer fans around the world, there’s been head-scratching over why a country like the United States, where the sport’s popularity is substantial but nowhere near that of American football or basketball, has taken the lead in investigating long-standing corruption allegations at FIFA.

The president of the United States Soccer Federation, which voted against Blatter in last Friday’s vote, said the resignation "represents an exceptional and immediate opportunity for positive change."

"This is the first of many steps towards real and meaningful reform within FIFA," said Sunil Gualti in a statement. "Today is an occasion for optimism and belief for everyone who shares a passion for our game."